FOURTH GENERATION [1971 ....]

Key Software Technologies	Somerepresentative System	Key Hardware Technologies	Key Characteristic
· Operating system for PCs with GUI and multiple windows on a single terminal screen · PC, Supercomputing applications and Network- based · UNIX operating system with C programming language · Multiprocessing OS with concurrent programming language · Object- oriented design and programming	· IBM PC AND ITS CLONES · CRAY - X/MP · VAX 9000 · APPLE II · CRAY - 2 · TRS - 80 · CRAY - 1	· ICs with VLSI technology · Microprocessors, semiconductor memory · Spread of high - speed computer networks · Magnetic tapes and floppy disks as portable storage media · Super computer based on parallel vector processing and symmetric multiprocessing technologies · Larger capacity hard disks as in - built secondary storage · Personal computers	· Small affordable, reliable and easy to use PCs · Rapid software development possible · More powerful and reliable mainframe systems and supercomputer · Easier to upgrade · Easier to produce commercially · Totally general purpose machines